Heat exchangers



a 3, 1967 1. LAING ETAL 3,295,597

HEAT EXCHANGERS Filed Jan. 12, 1962 4 Sheets-Sheet 1 INVENTORS INGEBORG LAING NIKOLAUS LAING BY%WI war/m, 2 2M ATTORNEYS Jan. 3, 1967 LMNG ETAL 3,295,597

HEAT EXCHANGERS 4 Sheets-Sheet 2 Filed Jan. 12, 1962 INVENTORS INGEBORG LAING ATTORNEYS NIKOLAUS LAING BY g; 4

1967 l. LAlNG ETAL 3,

HEAT EXGHANGERS Filed Jan. 12, 1962 4 Sheets-Sheet 5 INVENTORS INGEBORG LAING NIKO Au's L A lNG Jan. 3, 1967 l. LAING ETAL 3,295,597

HEAT EXCHANGERS Filed Jan. 12, 1962 4 Sheets-Sheet 4 INVENTORS INGEBORG LAING 77 NIKOLAUS LAING AT TO RNEYS United States Patent 3 Claims. (a. 165-86) The invention relates to rotary heat exchangers for exchange of heat between two fluid media; the invention relates also to rotors which may form, or form part of, such heat exchangers. One form of rotary heat exchanger is shown in U.S. patent application Serial No. 249,064 filed January 2, 1963 and being a continuation-in-part of application No. 701,600 (now abandoned) filed December 9, 1957.

The invention is concerned in particular with providing rotor structure for a rotary heat exchanger which will insure a maximum exchange of heat between a fluid mechanism passing through the structure of the rotor and a second fluid medium passing over the exterior of the rotor. Broadly the rotor of the invention comprises a plurality of hollow rib-like members which are coaxially spaced along the rotor axis and which have a plurality of axially extending hollow blade elements connecting the interiors of adjacent ribs. The blade elements in turn form axially extending fluid conduits which serve as inflow and outflow conduits for a fluid medium which is passed through the rotor with the inflow and outflow conduits being alternatively and circumferentially spaced. An inlet fluid manifold means is provided at one end of the rotor and is connected with the inflow conduits while an outlet fluid manifold is provided at the same end of the rotor and is connected with the outflow conduits. When a first fluid medium is forced through the inlet manifold, fluid will then flow through the inflow conduits, through the hoilow rib members into the outflow conduits and thence into the outlet manifold. A second fluid medium, for example air, may be passed over the blade elements and hollow ribs making up the rotor in order that heat will be exchanged between the two media. These connections will generally run in the circumferential directions and will be arranged at more or less equal intervals in the direction of the axis of rotation.

This arrangement increases the surface of the rotor available for heat exchange by reason of the wall surfaces of the transverse connections between the blade element of the rotor. The first fluid medium flows past the inside of these additional wall surfaces and the second fluid medium flows past the outside. With this arrangement, the additional heat exchange surfaces oflter only a slight resistance to heat flow in comparison with an arrrangement wherein solid extensions are provided on the blades to increase the heat exchange area. The fluid connections advantageously consist of hollow ribs which are annular and arranged coaxially with the axis of rotation of the rotor of the fan and at equal intervals along the latter.

In rotors constructed in accordance with the invention there is the additional advantage that the ends of the blades remote from the blade inlet and outlet means may be closed, whereas the corresponding parts of known heat exchangers must be provided with connecting means at that end of the rotor between the two groups of blades.

A number of examples of the invention are illustrated diagrammatically in the drawing.

FIGURE 1 is a cross section through a portion of a rotor, with tubular transverse connections.

3,295,597 Patented Jan. 3, 1967 FIGURE 2 is a perspective view of a portion of the arrangement illustrated in FIGURE 1.

FIGURE 3 is a perspective view of a portion of a rotor of a second example with transverse connections in the form of hollow ribs.

FIGURE 4 is an exploded perperspective View of the arrangement shown in FIGURE 3 but rotated through FIGURE 5 is a top plan view of a portion of a single rib of a fan rotor of a third example, provided with transverse connections in the form of hollow ribs.

FIGURE 6 is a section on the line VIVI in FIGURE 5 through the rotor of the third example.

FIGURE 7 is a cross-sectional view of a rotary heat exchanger having therein a rotor constructed according to FIGURE 6, and FIGURE 8 is a cross-sectional view similar to FIGURE 6 of a further rotor construction.

FIGURE 1 shows a cross section through a portion of a rotor of a rotary heat exchanger, in which a first fluid medium e.g. hot water which has performed some cooling function, flows out through hollow blades 10 parallel to the shaft 11 of the rotor, and flows back in cooled condition through the hollow blades 12. The blades 10 and 12, which are constructionally similar, alternate and are'mounted in a ring about the shaft 11 so as to extend parallel thereto. At one end of the rotor these blades 10 and 12 open into an annular duct 13, fixed to the end disc 14 connected with the shaft 11. At the other end of the rotor the blades 10 are connected with a fixed inflow device and the blades 12 with a fixed outflow device for the first fluid medium through shaft sealings in a manner not shown in the drawing. Narrow connecting tubes run between the blades 10 and 12 in a generally circumferential direction. In operation, a second fluid medium, e.g. air is forced to flow over the blades 10 and 12 and the tube 16 by virtue of the fact that the rotor operates as a .fan.

Each of the blades 10 which carry hot water is connected through these narrow connecting tubes 16 with its two adjacent blades 12 which carry cooler water. The connecting tubes are so designed that the flow resistance is such that there will still be a significant flow of first heating medium parallel to the rotor shaft 11 in the ends of the blades 10 and 12 adjacent to the annular duct 13.

FIGURE 2 is a portion of the arrangement in FIG- URE 1, showing the blades 10 and 12 connected by a large number of connecting tubes 16 which lie in planes of rotation and are arranged at equal intervals 18 in the direction of the shaft 11 which is not shown in FIG- URE 2.

FIGURES 3 and 4, show, viewed in perspective, portions of a rotor of a second example, FIGURE 4 showing the arrangement in the extended position. The rotor consists of a stack of similar pairs of rings 50, 51 and 52, 53, the rings of each pair being a mirror image of one another. The blades of the rotor are composed of short blade sections which consist of hollow integral projections 54, 55 on the rings 54 to 53. The rings 50 to 53 are annularly dished and the inner edges of the rings of each pair are secured together so as to define between them a hollow rib having an annular duct 59. The hollow projections 54, 55 are arranged on the dished central annular portion 56 of the rings, and have their free ends 57 connected together. The annular duct 59 is formed between two adjacent rings, this duct connecting the insides of the different hollow blade forming projections to each other. Thus the first medium flows through one set of hollow projections 54, 55 and back through another set of the projections. The first medium can also pass through the annular ducts 59 from one blade 54 to an adjacent blade. In order to ensure that those sections of a blade which are far removed from the inflow and return flow devices (not shown) for the blades 54 will still contain an adequate flow in the longitudinal direction the dished portions 56 are provided with projections 60 in the form of bars arranged between adjacent projections 54. These projections considerably reduce the crossasection of the annular duct 59 and form a barrier to the medium flowing through the duct 59.

FIGURES and 6 illustrate a third form of rotor for a rotary heat exchanger having a series of rings 70 which differ from the rings shown in FIGURES 3 and 4 by the fact that between the hollow blade projections 71 they are provided not only with projections 72 forming a barrier for the first fluid medium but also with several ridges 73 which increase the surface of heat exchange of the annular duct 74 formed by the rings 70. In addition, the blades may be so designed that the space between adjacent blades has a resistance towards the suction end of one blade which is substantially different from that towards the pressure end of the other blade. The velocity of the second fluid medium may thereby be uniformly distributed over the periphery, the noise during operation being thereby considerably reduced.

FIGURE 7 shows a rotary heat exchanger incorporating the third form of a rotor above referred to, and here shown in full and designated 100. The rotor is built up of a stack of the rings 70 assembled between end members 101, 102 secured together by rods 103 passing through certain of the aligned blade-forming projections 72 of the stack as indicated in FIGURE 4. The rings 70 are alternatively of left-hand and right-hand character designated 70a, 70b; on one side of a ring 7011 it is secured to the adjacent ring 70b at inner and outer peripheries while at the other side the blade forming projections 72 are secured to the opposite projections 72 of the next ring 70b on that side. The blade-forming projections are aligned to form a plurality of conduits 104 extending longitudinally of the rotor between the end members 101 and 102, and these conduits are interconnected by the annular ducts 74 formed by the pairs of rings 70.

The rotor 100 is mounted in an overhung position on a shaft 105 which is driven by a V-belt pulley 106 and joumalled in bearings '107 mounted in a housing of which part only is shown at 108.

Manifold means designated generally 110 are provided at the end of the rotor opposite the shaft 105 and serve to feed liquid into the rotor, and to remove it therefrom.

The end member 102 of the rotor includes a distributor 111 in the form' of a thick hollow disc which communicates with alternate ones 104a of the conduits 104. Liquid is supplied axially to the distributor 111 by means of a stationary pipe 112 projecting axially into the rotor end member '102. Liquid accordingly flows from the pipe 112 into the distributor 111 and thence outwardly along conduits 104a towards the other end of the rotor. The rotor end member 102 further includes a collector of generally conical formation and designated 113 which surrounds the distributor 111 and communicates with conduits 104b between the conduits 104a. Liquid flowing in the conduits 104a is bled off all along the length of the rotor through the annular ducts 74 into the conduits 104b and returns through these conduits 104b to the collector 113 and thence through a rotary seal not 5 shown and concentric with the pipe 112 into a stationary 4 duct 114. Baflles 115 in the distributor 111 and 116 in the collector 113 are provided to facilitate flow.

As has been explained, the pairs of opposed bladeforming projections 72 constitute a series of blades dis-- posed in a ring around the rotor axis. Guide means designated generally 120 surround the rotor 100 and cooperate with the rotor on rotation thereof to produce a flow of air from a suction side through the path of the rotating blades of the rotor to the hollow interior thereof and thence again through the path of the rotating blades to the pressure side of the rotor, the flow taking place along lines transverse to the rotor axis. The ridges 73 are also of blade formation and assist the flow described.

FIGURE 8 shows an arrangement similar to that shown in FIGURE 6 but with considerably deeper ridges 92. The rings, which are arranged symmetrical-1y as mirror images of one another, are soldered or welded together along the line 93, corresponding to the line 72 in FIGURES, and along 94 and 95.

We claim:

1. A rotor adapted for use in a rotary type heat exchanger to eflect heat exchange between a first and seca 0nd fluid medium, said rotor comprising a plurality of hollow annular shaped coaxially spaced ribs, a plurality of parallel circumferentially spaced hollow blade elements extending axially between and connecting the in- -terior of adjacent hollow ribs to form axially extending circumferentially alternatively spaced inflow and outflow fluid conduits extending over the axial length of the plurality of rib members, an inlet fluid manifold means at one axial end of the plurality of hollow ribs connecting with said inflow fluid conduits, and an outlet fluid manifold means at the same axial end of said hollow ribs as said inlet manifold connecting with said outflow conduits; a first fluid medium upon being forced into said inlet manifold flowing through said inflow conduits and being progressively bled off therefrom by said hollow.

ribs and thence flowing through said outflow conduits to said outlet manifold whereby heat may be'exchanged between said first fluid medium and a second fluid medium passing over the exterior of said hollow ribs and,

blade elements.

2. A rotor as claimed in claim 1, wherein the ribs are formed with projections to extend the area for heat exchange With the second medium.

3. A rotor as defined in claim 1, wherein the blade elements are closed at the end ,of said rotor opposite.

said manifold means.

References Cited by the Examiner UNITED STATES PATENTS 11/1931 MacLean 158-87 ROBERT A. OLEARY, Primary Examiner.

FREDERICK L. MATI'ESON, JR Examiner. T. W. STREULE, Assistant Examiner. 

1. A ROTOR ADAPTED FOR USE IN A ROTARY TYPE HEAT EXCHANGER TO EFFECT HEAT EXCHANGE BETWEEN A FIRST AND SECOND FLUID MEDIUM, SAID ROTOR COMPRISING A PLURALITY OF HOLLOW ANNULAR SHAPED COAXIALLY SPACED RIBS, A PLURALITY OF PARALLEL CIRCUMFERENTIALLY SPACED HOLLOW BLADE ELEMENTS EXTENDING AXIALLY BETWEEN AND CONNECTING THE INTERIOR OF ADJACENT HOLLOW RIBS TO FORM AXIALLY EXTENDING CIRCUMFERENTIALLY ALTERNATIVELY SPACED INFLOW AND OUTFLOW FLUID CONDUITS EXTENDING OVER THE AXIAL LENGTH OF THE PLURALITY OF RIB MEMBERS, AN INLET FLUID MANIFOLD MEANS AT ONE AXIAL END OF THE PLURALITY OF HOLLOW RIBS CONNECTING WITH SAID INFLOW FLUID CONDUITS, AND AN OUTLET FLUID MANIFOLD MEANS AT THE SAME AXIAL END OF SAID HOLLOW RIBS AS SAID INLET MANIFOLD CONNECTING WITH SAID OUTFLOW CONDUITS; A FIRST FLUID MEDIUM UPON BEING FORCED INTO SAID INLET MANIFOLD FLOWING THROUGH SAID INFLOW CONDUITS AND BEING PROGRESSIVELY BLED OFF THEREFROM BY SAID HOLLOW RIBS AND THENCE FLOWING THROUGH SAID OUTFLOW CONDUITS TO SAID OUTLET MANIFOLD WHEREBY HEAT MAY BE EXCHANGED BETWEEN SAID FIRST FLUID MEDIUM AND A SECOND FLUID MEDIUM PASSING OVER THE EXTERIOR OF SAID HOLLOW RIBS AND BLADE ELEMENTS. 